Malicious PDF — malware analysis report

Static analysis result for SHA-256 870d359d78602256…

MALICIOUS

PDF

81.9 KB Created: 2021-09-12 22:26:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4dc8cb2bf6a868175a76286e7950c5e6 SHA-1: 98c72dd014521a59d03872e409c8f21fd4f87f98 SHA-256: 870d359d786022568e6252f448e8b202b67c450c4fd1fde7f9a13d3a7bc650ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised WordPress uploads or disposable hosting, suggesting it functions as a link farm to distribute malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect users to harmful sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://smidgel.ru/uplcv?utm_term=average+rate+of+change+linear+function PDF link annotation
    • http://ropesadventure.com/d/files/voxomokizajekibijajided.pdfIn PDF document text
    • http://varadimasszazs.hu/uploads/files/welopenewoxerurejefitazaj.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d96a953855---68526899399.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/84897356614.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/60829605882.pdfIn PDF document text
    • http://ecole.ru/text/images/file/67098931837.pdfIn PDF document text
    • http://www.celso.org/download/vixonipes.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/161329ee035e7c---74392267402.pdfIn PDF document text
    • http://bretagne.annuaire-regional.com/ckfinder/userfiles/files/62826401169.pdfIn PDF document text
    • http://jmlukanich.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gumolaka.pdfIn PDF document text
    • http://www.polni.si/Images/files/tesaluf.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/baqd5d51qfq34q6cae09eo15es/13015291982.pdfIn PDF document text
    • http://sun-green.eu/ckfinder/userfiles/files/78515363362.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/161322760dafb0---xiwazimikezeb.pdfIn PDF document text
    • http://fittbikese.hu/files/file/57160197045.pdfIn PDF document text
    • https://dalilak1.com/userfiles/file/83801032926.pdfIn PDF document text
    • http://hykylalumni.org/userfiles/36506180463.pdfIn PDF document text
    • http://guchen.ru/d/files/23301795642.pdfIn PDF document text
    • http://iktoktatas.hu/files/file/21747012819.pdfIn PDF document text
    • http://studiotecnicodavico.eu/userfiles/files/30470730359.pdfIn PDF document text
    • https://charteriraq.ir/basefile/charteriraqir/files/misinitujofozolamolame.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/kajumaxi.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///89263515486.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d8f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F4 10592 bytes
SHA-256: cc1160691d2f09698f7b14777063d646603c09928ab87db8c604065e37591987
font_01_sfnt_off0000f118.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF118 18640 bytes
SHA-256: f77dd401ed48ecf0cef95140b4046ab5f1e512c06ce3ca4ba71657c70fd85ace
font_02_sfnt_off00012251.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12251 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1